The present invention relates to microfluidic devices, and more particularly, to the sealing layers between with a device and a method of forming seals on a microfluidic device.
Methods of making a homologous series of compounds, or the testing of new potential drug compounds comprising a series of light compounds, has been a slow process because each member of a series or each potential drug must be made individually and tested individually. For example, a plurality of potential drug compounds is tested by an agent to test a plurality of materials that differ perhaps only by a single amino acid or nucleotide base, or a different sequence of amino acids or nucleotides.
The processes described above have been improved by microfluidic chips which are able to separate materials in a micro channel and move the materials through the micro channel. Moving the materials through micro channels is possible by use of various electro-kinetic processes such as electrophoresis or electro-osmosis. Fluids may be propelled through various small channels by the electro-osmotic forces. An electro-osmotic force is built up in the channel via surface charge buildup by means of an external voltage that can repel fluid and cause flow.
In fluid delivery in microfluidic structures, several layers comprise the device. Channels often extend between the various layers. Because the fluid is under pressure, sealing the layers together to prevent leakage and cross contamination is extremely important.
Currently, the method for fabricating seals is very labor and time intensive. Therefore, the seals are not cost effective. For example, to fabricate a seal pattern with 144 seals takes in excess of 4 man hours. The current technology push is to develop microfluidic devices that have hundreds and even thousands of reaction chambers per cell. More reaction wells increases the need for effective and robust seals.
It would therefore be desirable to reduce the cost, time and labor associated with the fabrication of seals for microfluidic chip assemblies.
It is, therefore, one object of the invention to provide an improved fluid delivery mechanism to an array of reaction wells.
It is a further object of the invention to reliably seal the various layers. It is a further object of the invention to reduce the amount of labor and time and therefore cost in the production of seals.
In one aspect of the invention, a method of forming seals comprises:
thinning a seal material between a first film and a second film;
cutting holes in the seal material;
applying the exposed seal material surface to a first substrate;
curing the seal material; and
removing the second film from the seal material.
One advantage of the invention is that the method of making seal layers may be automated to be more time efficient and therefore more cost effective.
Other objects and features of the present invention will become apparent when viewed in light of the detailed description of the preferred embodiment when taken in conjunction with the attached drawings and appended claims.